Field installation versus local integration of photovoltaic systems and their effect on energy evaluation metrics

In this study we employ Life‐Cycle Assessment to evaluate the energy‐related impacts of photovoltaic systems at different scales of integration, in an arid region with especially high solar irradiation. Based on the electrical output and embodied energy of a selection of fixed and tracking systems and including concentrator photovoltaic (CPV) and varying cell technology, we calculate a number of energy evaluation metrics, including the energy payback time (EPBT), energy return factor (ERF), and life‐cycle CO2 emissions offset per unit aperture and land area. Studying these metrics in the context of a regionally limited setting, it was found that utilizing existing infrastructure such as existing building roofs and shade structures does significantly reduce the embodied energy requirements (by 20–40%) and in turn the EPBT of flat‐plate PV systems due to the avoidance of energy‐intensive balance of systems (BOS) components like foundations. Still, high‐efficiency CPV field installations were found to yield the shortest EPBT, the highest ERF and the largest life‐cycle CO2 offsets–under the condition that land availability is not a limitation. A greater life‐cycle energy return and carbon offset per unit land area is yielded by locally‐integrated non‐concentrating systems, despite their lower efficiency per unit module area.